code: def test_pickle(self) -> None:
      for dtype in (torch.float, torch.double):
          tkwargs = {"dtype": dtype, "device": self.device}
          posterior = TorchPosterior(
              Exponential(rate=torch.rand(1, 2, **tkwargs))
          )
          with tempfile.NamedTemporaryFile() as tmp_file:
              torch.save(posterior, tmp_file.name)
              loaded_posterior = torch.load(tmp_file.name)
          self.assertEqual(posterior.dtype, loaded_posterior.dtype)
          self.assertEqual(posterior.device, loaded_posterior.device)
          self.assertTrue(
              torch.equal(
                  posterior.distribution.rate,
                  loaded_posterior.distribution.rate,
              )
          )
  
file_path: botorch/test/posteriors/test_torch_posterior.py
imports: import os
  import tempfile
  import unittest
  import torch
  from botorch.posteriors.torch import TorchPosterior
  from botorch.utils.testing import BotorchTestCase
  from torch.distributions.exponential import Exponential
label_desc: Use image node_id 2 for calling the TestTorchPosterior obj's underlying member method code with example usage: obj.test_pickle() without return types